Vibration-dampening device



June 24, 19 30. E. o. ACKERMAN 1,765,477

VIBRATION DAMPENING DEVICE Original Filed Oct. 12, 1927 2 Sheets-Sheet 1II III;

ATTORNEY June 24, 1930. E. o. ACKERMAN 5,

VIBRATION DAMPENING DEVICE Original Filed 001:. 12, 1927 2 Sheets-Sheet2 o INVENTOR [If O.Ackerr\1ar\ k- BY ATTORNEY by prevent railcorrugation.

Patented June 24, 1930 titan? ELI O. ACKERMAN, F COLUMBUS, OHIO IVIBRATION -DLAMPENING DEVICE Original application filed October 12,1927, Serial No. 225,995, now Patent No. 1,718,100, dated. June 13.,

1929. Divided and this application filed June 10, 1929. SerialITO/369,550.

L ling the torsional vibratory action of the individual units of railwayrolling stock and the. present invention is a division of saidapplication.

Asmore fully explained in said copending application, the corrugation ofrails of electric railway lines has been found to be due to cumulativetorsional vibrations set up in the traction units of the cars as thecars are being driven over the line and repeatedly occurring at certainpoints alongthe line.

l The present invention has for its object to prevent such cumulativetorsional vibrations in the traction units, composed of driving axlesand attached traction wheels, and there A further object is to provide adampening device which is, adapted'to be mounted on a traction unitwithout altering the axle mounting or axle driving connections.

. With the above and other objects in view, the invention maybe said tocomprise the vibration dampening device as illustrated in theaccompanying drawings hereinafter described and particularly set forthin the appended claims, together with such variations .andmodificationsthereof as will be apparent to one skilled in the art to which theinvention appertains. v Reference should be had to the accomp anyingdrawings in which: K

Figure 1 is a side elevation of a vibration dampener embodying theinvention appliedv to a car axle.

Fig. 2 is asection taken on the line indi- 150 sated at 2.2 in Fig. 1.

fled form of vibration dampener.

Fig. 4 is a sectional View showing a vibration dampener applied to a carwheel.

Fig. 5 is a side elevation of the car Wheel with the dampener mountedthereon.

Fig. 6 is a radial section through a car wheel having a modified form ofdampener thereon. I

The present invention, as illustrated in the accompanying drawingsconsists of a vibration dampener of the fly-wheel type which is mounteddirectlyjon either the axle or one or both of the wheels attachedthereto.-

The vibration dampener shown in Figs. 1 and 2 consists of a flywheel 1,divided into two parts which are held apart by means of a series of coilsprings 2. 'The flywheel is mounted in a flanged hub 8 which is keyed tothe axle and which carries a flanged collar of pins 8 which are fixed toone section and project into sockets formed in the other section. Thesprings'EZ hold the two parts of the flywheel against the pieces offriction .70 4, which is screwed on the hub and held in fabric 6 and 7with whatever pressure is re quired and the pressure is adjustable byturning the collar nut e and looking it in adjusted position with the jam nut 5. The flywheel 1 may revolve independently of the hub and axleand when the axle revolves, the flywheel will be driven through thefriction fabric-face members 6 and 7. Should any attemptbe made toquickly reverse the direction of revolution of the axle, the momentum ofthe flywheel 1 will oppose such attempt. When the spring pressure isadjusted so that the fabric will slip at the alternating speed ofnatural torque vibration of wheels and axle, the inertia of the flywheelwill serve as held between a flange on a hub 10 and a flange nut 11 onthe hub which is held in adjusted position by bolts 12 instead of by ajam nut as shown inFigs. 1 and 2.

Fig. l shows adaptation of vibration dampener for attachment directly toa car wheel, this dampener being useful where there is not sufiicientroom on the axle to mount a dampener such as shown in Figs. 1 and 2. Inthis form,'the flywheel consists of inner andouter sections 13 and 14.which are pressed apart by coils'prings 15. Section 13 of the flywheelis of substantially wedge form in radial section to flt against theinner face of the web of the car wheel and is pressed against an annularpiece of friction fabric 16. The inner section 14 is pressed against asimilar annular piece of friction fabric 17 secured upon the inner faceof a flange nut 18, which is screwed upon the hub of the wheel and heldin adjusted position by means .of bolts 19 extending through the plateand the web of the car wheel.

- The traction unit to which the various forms of vibration dampenersherein illustrated are applied consist ofa driving axle with tractionwheels fixed to the opposite ends thereof.

Figs. 1 and 2 show the dampening device attached directly to the axleand Figs. 3 to 6 show dampening devices mounted on the traction wheels.In electric railway cars, the traction units are driven from a suitablemotor'through spur gearing such. as illustrated in Fig. l in which thereis shown a large spur gear 20 fixed to the axle which is driven by apinion 21 fixed to a suitable drive shaft 22. As more fully explainedinmy copendino' application above referred to, the driving gears tend toset up torsional vibrations in the traction units which, at certaincritical speeds, become cumulative and have a rail deforming actionproducing corrugations in the rail treads.

Figs. 5 and 6 show a similar form of'dampener adapted to be attacheddirectly to alcar wheel and in this form, the flywheel 23 is formed inone piece with its, outer fac'e'of substantially conical form to conformto the inner face of the web of thecar wheel. The flywheel bears againstan annular piece of friction fabric 2 1 secured upon theface of the carwheel and is yieldingly pressed toward the car wheel by means of anannular plate 26 which has a central opening provided with notches 27,which receive lugs of similar form formed on the hub of the car wheel.The plate 26 carrieson itsinner face an annular piece of friction fabric28 and the torsional" for dampening torsional vibrations in said isyieldingly pressed toward the flywheel to clamp the flywheel between thefriction fabric on the car wheel and the friction fabric on the plate bymeansof bolts 29, carrying springs 30, which serve to maintain a springpressure on the plate 26! to maintain pressure between the flywheel andthe friction fabric on opposite sides thereof.

It will be apparent that in'each of the modifications above described,the action of the flywheel is to dampen torsional vibraticns and preventsuch vibrations from becoming cumulative so that the traction wheelswill not have a rail deforming'action atany speed at which they may bedriven over the rails. It will also be apparent that the dampeningdevice of the present invention is of simple and inexpensiveconstruction'and can be applied to a car wheel or car axle withoutalterations in the mounting of the, car axles and without any change inthe driving con nections to the axle.

hat I claim is: I V

1. In a power driven railway car, the comr bination with a driving axleand the traction wheels fixed thereto, of means for driving the axle,and means for dampening torsional vibrat-ions in said axle and attachedtraction wheels.

2. In a power driven railway car, the combination with a driving axlehaving traction wheels and a spur gear attached tothe axle between oneof the wheels and the longitudinal center of the axle, of a drive shafthaving a pinion meshing with said gear, and means axle and attachedtraction wheelsfl I 3. In a power driven railway car, the com: binationwith a driving axle having traction wheels and a spur gear attachedtothe axle between one of the wheels and the'longitudinal center of theaxle, of a drive shaft having a pinion meshing with'said gear, and meansmounted on a traction wheel for dampening torsional vibrations in saidaxle and attached traction wheels. Y

4t. Ina power driven railway car,a rotat- I able traction unitcomprising a driving axle and traction wheels attached thereto, and a.dampener comprising a flywheel mounted on said unit and rotatablerelatively thereto,and frictional means opposing relative rotationbetween said flywheel and unit.

5. In a power driven railway car, a-rotatable traction unit comprisingan axle and traction wheels fixed to the axle, and means for "dampeningtorsional vibrations insaid unit comprising aflywheel and means forminga frictional. driving connection between said flywheel and unit. p f

6. In a power driven railway car, the corn bination with a tractionwheel, of avibra tion dampener comprising a flywheel and means forming africtional driving connection between the traction wheel and flywheel..130

7. In a power driven railway car, a rotatable traction unit comprisingan axle and traction wheels fixed to the axle, a flywheel rotatable withrespect to said axle, a member fixed with respect to said axle and infrictional engagement with said flywheel and means for varying thepressure between said member and flywheel.

8. In a power driven railway car, a driving axle, a traction wheelhaving a rail en gaging tread, a hub fixed to the axle and a webconnecting the tread and hub, a disc fixed to the hub and spacedinwardly from the web, a two part flywheel mounted between said web anddisc, springs interposed between the parts of said flywheel for pressingthe same against said web and disc, and means for ad justing said disctoward and away from said web to vary the pressure between the parts ofthe flywheel and the web and disc.

9. In a power driven railway car, a driving axle, a tractionwheel havinga rail engaging tread, a hub fixed to the axle and a web connecting thetread and hub, a disc fixed to the hub and spaced inwardly from the web,a two part flywheel mounted between said web and disc, springsinterposed between the parts of said flywheel for pressing the sameagainst said Web and disc, friction material interposed between theflywheel and the web and between the flywheel and disc, and means foradjusting said disc toward and away from said web.

In testimony whereof I aflix my signature.

ELI O. ACKERMAN.

